A．During the course of operation, water in the battery electrolyte will reduce because of electrolyzation and evaporation so that electrolyte level reduces. If pure water is not filled into the battery in time, service life of battery plate will be shortened. Check it regularly and fill pure water in time.

B．The battery can be filled with pure water within 1-2 hours after charging is complete. It is not allowed to fill pure water before charging and during the course of charging.

Normal electrolyte level as follows:

2. check specific gravity regularly

Measuring steps: open filling plug and insert a hydrometer to absorb a little electrolyte so that the dobber in the hydrometer floats, make sure top end of the dobber does not touch rubber ball and outer wall of pipe. Put the hydrometer straight, gaze at liquid level horizontally: at recession, the scale on the dobber is the value of specific gravity. Specific gravity of the electrolyte is related to the temperature. Measure electrolyte temperature.

Standard value: at 20℃, the density is 1.28kg/L

DC motor maintenance

1. Check the motor once every six months according to the following methods.

A、Remove dirt, deposited ash and carbon (carbon ash due to electric brush wear) from the motor to facilitate normal work and heat radiation of the motor;